The giant salamanders belongs to the family cryptobranchidae which includes two genera, Andrias and cryptobranchus. There is Andrias japonicus in Japan, A. davidianus in China and Crytobranchus alleganiensis in North America (Fig.1).

　　Fig.1. Distribution map of the family Cryptobranchidae.

　　1. China
　　Chinese Giant salamander (Andrias davidianus)
　　Features: Andrias davidianus is the largest species of all amphibians with a total body length of 1.8~2.0m and a weight of 20~25kg. The maximum record to weight is over 100kg. During the mating season, it often cries. Its crying sound is like that of a baby, therefore, it is often called “wawa fish ”(baby fish) by common people in China. It has a big and flat head, on which there are apparent grains. Andrias davidianus has a large mouth, but its eyes and nostril are very small. Its tail is flat and its skin is soft and smooth. It has flesh folds of skin along the sides of its body. Its skin color of back is brown and ones of abdomen is light. Its four limbs are short and fat, with four fingers on anterior limb and five toes on the posterior ones.
　　Chinese Andrias distinguished form Japanese Andrias with next three characteristics. This species has many pairs of warts on head, blotches on the colored back, eyes stands out.
　　Habitat: Andrias davidianus resides in mountain streams in-between el. 200~1500m, where the water is rapid, clear and where there are many cracks and holes on rocks, usually seldom have human beings come.
　　Feeding habits: Adrias davidianus won’t attack positively to got its food, instead, it will open its mouth to wait for its prey to enter its mouth. It likes to eat fish, crabs, frogs, snakes and other aquatic animals.
　　Breeding: The mating season of Andrias davidianus is from June to August each year, and it lays its eggs on rocks. The eggs are enveloped in chalazae, like a string of beads. The breeding adult has the habit to protect eggs. The eggs accept sperm outside and larvae will be hatched out within 21days naturally. The larvae grow very slowly.
　　Category: Amphibia, Urodela, Cryptobranchidae.
Distribution: In the long narrow bow-shape area across Guizhou, Hunan, Hubei, Sichuan and Shanxi provinces and in the limestone mountain area in the part of the middle and lower reaches of Yangtze River.

　　Fig 2. Distribution map of Andrias davidianus in China .
Protection level: Since its flesh is delicious, it incurs wanton over killing. The number of giant salamanders is reducing in all original habitats and it even becomes distinct in some places. It has been listed as Class II state protection animal and in Appendix I of CITES.
　　2.Japan
　　Japanese Giant Salamander (Andrias Japonicus ).
　　Features: Japanese giant salamanders are large aquatic salamander that usually reachs 40-70cm TL, specimens over 100cm thing are very rare. The maximum record in Hiroshima is 140cm TL, over 20KG!!! This huge Andrias is female and keeping at the Takamiya Eco Museum. It is said that a specimen over 160cm was caught in Shiga Prefecture, that rumor remains to be confirmed.
　　Japanese giant salamanders are dark brown with black spots on it’s back and the belly is lighter than the back. It has fleshy folds of skin along each side of the body. The head is warty and eyes are inconspicuous as their grow. The gill slits close after transformation.
　　The Japanese name of this species are “Osanshouuo”,“Hanzaki”,“Hajikamiio.” These are named for their produce mucous from the skin that smell like a Japanese pepper(=sansho, hajikami).“Honzowamyo(918A.D.)”is the oldest book that involved a“Hajikamiio”story.
　　In 1829, the specimen that Philipp Franz von Siebold brought to the Netherland was about 70cm TL. It lived for 51 years. It is said that Japanese giant salamanders have a long life about over 70 years.
　　Japanese giant salamanders are active at night and hide under rocks or in the holes at the side of banks in the daytime, They eat clabs, fish, frogs, snakes and mice. Larvae utilize stones and fallen leaves in slow-moving streams.
　　Habitat: This species is found in mountain streams 300 to 700m, where the water is cold clear and rapid .The streams have rocky bottoms and bank with borrows. In Hiroshima, the width of streams are usually about 10m. Also it occurs less than 5m from sites that include breeding locations. Currently, adults A. japonicus barely survive the horrible river conditions. There are few chances for these magnificent creatures to reproduce because of habitat degration.
　　Breeding: In late August to early September, the breeding occurs in time of less than the water temperature 20 degrees. The breeding nest are usually in the holes at the side of banks near the source of streams. The breeding behavior was obserbed only once in Hiroshima by the Asa Zoo in 1978. A large male occupies the nest and a female comes into the nest with some other males. Five females laid in the same nest for three days. There were 18 males and 9 females in the breeding group. The smallest male and female were respectively 30cm and 40cm in total length. They gathered in nests in the river bank as far as 30~600m from their own territories. After fertilization, The largest males occupied a nesting site and guarded a 2~3m radius around it. They then fought off other males awaiting potential mates until eggs hatched.
　　A female deposits 500~600 eggs for two or three hours. The larvae hatch in about 50~60 days, they stay immobile until about January and then leave the nest little by little. Larvae were found in and around the nest to as far as 600m downstream at the Asa Zoological Park. The larvae measured 60~70m TL in late June and then disappeared. Larger larvae never been found. The larvae transform in 3~4 years at about 20 cm. They become sexually mature in capitivity about 10 years.
　　The Asa Zoo team succeeded breeding this species in captivity after wild breeding observations were recorded. Dr Jiro Kobara describes captive breeding of A. japonicus in detail in his book (Kobara, 1988).
　　Category: Amphibia, Urodela, Cryptobranchidae.
Distribution: Mainly distributed in the south Honshu and fractionally in Shikoku and Kyushu (Fig. 3).

　　Fig. 3. Distribution map of Andrias japonicus in Japan, adapted and redrawn from Kobars(1985).
　　Status: Andrias japonicus is one of the most threatened animals in Hiroshima. It was once very common in the Cugoku Mountains. Peaple usually ate them and kids caught larvae in small streams 40~50 years ago (Utsunomiya, 1998). It was an important source of food for mountain people until several years ago. It is said that the taste is like a ray or a shark. The Japanese giant salamanders probably declined everywhere. Now this species is a Japanese national special tresure and be prohibited even touch by low. It is the rare species of RDB Hiroshima, NT of Environment Agency, VU of IUCN, and classified a CITES I species (Tochimoto, 1996).
　　Conservation: Dams prevents their migration and separates their populations. With river quality in decline artificial nesting sites are being used. They are made of a pipe with a diameters of 20cm connected to a breeding bed with a diameters of 60cm, it has a cover and a peep-hole. In Hyogo Prefecture, some females lay eggs in this nest, but the eggs tend to die. The nest is also continually buried underground by river flow (Tochimoto, 1998).
　　3. America
　　Hellbender (Cryptobranchus alleganiensis)
　　Features: Hellbenders have a flat and fat body with a total body length of about 75cm and a weight of about 5kg. The whole skeleton of hellbender is greatly flattened, especially the skull. The lacrimal and septomaxillary bones had been lost. They have a flat head with a large mouth and a pair of tiny eyes without eyelid. On the head of adult hellbenders the spiracle remains opened as an outlet for water taken into the mouth during aquatic buccal respiration, unlike in adult Andrias the spiracle is closed. They do have lungs and are capable of gulping air from the surface, but they tend to do all of their breathing through their skin. Their skin is soft, smooth and slimy with a lot of mucous glands. They have flesh folds of skin along the sides of their body which help to take in oxygen from the water. They have a large, flat and very keeled tail which is very strong and powerful as the dynamic structure that helps to propel them through the water. The four limbs of them are short, very large and muscular with four fingers on the anterior limb and five toes on the posterior lomb. Hellbenders can range in color from dull brown or gray to bright orange or red. They usually have some sort of darker spots or blotches on their bodies, but the belly is usually only one color.
　　Habitat and Feeding Habits: Hellbenders are completely aquatic, and only rarely have been reported to come out of the water for any period of time——there are a few reports of them wandering across land during very heavy rains. Since hellbenders spend their entire lives in water they need to have streams that are cool enough and which have enough oxygen to sustain them. More specifically, hellbenders need clean, cool streams with many large rocks scattered on the bottom, they are usually found in smaller rivers and streams, in about 1~3 footdeep water. Rivers that have a mixture of faster flowing rapids, with slower moving runs and pools are ideal for these salamanders. Hellbenders hide under rocks or in the holes at the sides of stream banks under water during the day and are active at night. They eat worms, crustaceans, frogs and fish.
　　Breading: Hellbenders usually breed in August or September, but they may breed during winter in some Missouri streams. Nest sites are usually under large rocks where a male has excavated a large cavity. Sometimes many hellbenders can be found around a single nest site. Usually several males will wait around a nest rock in the fall, and some extremely fierce battles over who gets control of the rock (and therefore gets to fertilize the eggs)may take place between the larger males. The smaller males probably “lay low ”and may attempt to sneak into the rock and fertilize eggs when the larger male isn’t paying attention .Once a nest rock is chosen ,up to 2 or 3 femaies will deposit a few hundred eggs each in a strand which swell to a ping-pong ball size eventually. The male makes external fertilization after the eggs have already been deposited when the female is forced out of the nest. The male has the action to protect eggs. It stays with the eggs until hatching, which may take place in 8 to 12 weeks. The body length of larvae is 3cm. After 18 months when the larvae reaches 12.5cm, its gills disappear.
　　Category: Amphibia, Urodela, Cryptobranchidae. There are actually two subspecies of hellbenders: the eastern hellbender, Cryptobranchus alleganiensis alleganiensis and the Ozark hellbender, Cryptobranchus alleganiensis bishop.
Distribution: The eastern hellbender, Cryptobranchus alleganiensis alleganiensis, makes up most of the range of the hellbender. The Ozark hellbender, Cryptobranchus alleganiensis bishopi,is only found in the Ozark Mountains in southern Missouri and northern Arkansas.

　　Fig.4. Distribution map of Cryptobranchus alleganiensis in Americe.